How much support you need depends on your feet and ankles so it's not an easy question to answer. On a treadmill with a surface that absorbs impact I like lightweight "minimal" shoes. I don't need ankle support at all and the reduced weight eases stress on my knees. By comparison, my wife pronates really badly and has to wear running shoes with tons of support.

I find that incline makes shin splints more likely but other than that I haven't seen ant difference in the amount of support that's needed.

if you're on an incline the biggest thing you will notice is that if you are used to a heel lift and dont have one you'll likely get some achilles pain or PF. best way around this is to stretch the calves

That sucks, no running specialty stores at all in your area at all?

The problem with self diagnosis when it comes to gait analysis is its pretty much impossible. The angle or view and which you need to see movement needs to be from behind of or in front of your foot at ground level or close to. So unless you can detach you head, the only way it works is if you can videotape yourself on a treadmill. Views looking down dont do much to tell you anything.

Basically youll want someone whos done a gait analysis before to tell you what category of shoes you fall into so you know youll be in the correct shoes for your gait type and you can make a decision on comfort and shoe fit.